No other projectile drops straight down.
While it can be used to close quarters, I think it is a strategic addition to the ranged field.
A sprayable minefield in some respects. Perhaps if the projectile 'burned' on the ground for just a hair after hitting. Maybe .5 or less.
Another idea for a gun is one that seeds a plasma cloud that other guns can contribute too, and then something triggers it to burst and shower down a plasma rain.
How do I build and test weapons? I would like to contribute some sketches to the GPL.